A Petri dish with red agar on which grows a fungal strand in the shape of the element symbol for platinum (Pt). Credit: © CO-ADD
Key Points:
- A research team is trying to develop new metal-based antibiotics to address resistant fungal strains.
- In their study, many metal compounds demonstrated good activity against all fungal strains, and were up to 30,000 times more active.
- The lead author hopes the study will improve the reputation of metals in medical applications.
To encourage the development of anti-fungal and antibacterial agents, researchers at the University of Queensland in Australia have founded the Community for Open Antimicrobial Drug Discovery, or CO-ADD. The goal of the initiative is to find new antimicrobial active agents by offering chemists worldwide the opportunity to test any chemical compound against bacteria and fungi at no cost.
While the initial focus of CO-ADD has been on organic molecules that do not contain any metals. Angelo Frei at the University of Bern, is trying to develop new metal-based antibiotics with his research group. They have found that over 1,000 of the more than 300,000 compounds tested by CO-ADD contained metals.
“For most folks, when used in connection with the word ‘people’, the word metal triggers a feeling of unease. The opinion that metals are fundamentally harmful to us is widespread. However, this is only partially true. The decisive factor is which metal is used and in which form,” explains Frei, who is responsible for all the metal compounds in the CO-ADD database.
In their new study, Frei and his research team tested 21 highly active metal compounds against various resistant fungal strains. These contained the metals cobalt, nickel, rhodium, palladium, silver, europium, iridium, platinum, molybdenum and gold.
The most active compounds were then tested in a model organism, the larvae of the wax moth. The researchers observed that just 1 of the 11 tested metal compounds showed signs of toxicity, while the others were well tolerated by the larvae. In the next step, some metal compounds were tested in an infection model, and one compound was effective in reducing the fungal infection in larvae.
“Our hope is that our work will improve the reputation of metals in medical applications and motivate other research groups to further explore this large but relatively unexplored field,” said Frei. “If we exploit the full potential of the periodic table, we may be able to prevent a future where we don’t have any effective antibiotics and active agents to prevent and treat fungal infections.”
Information provided by University of Bern.